RU2559230C2 - Conduction of mockup tests for evaluation of disclosing properties of combat equipment - Google Patents

Abstract

FIELD: instrumentation.

SUBSTANCE: invention relates to semi-actual simulation of combat individual equipment (CIE) tests. Measurement of properties to be evaluated is performed in closed lab room. Normalized conditions of observation in spectrum near IR band are created by means of artificial illumination system. Natural fragments of standard natural background are used with steady-state reflection factors in CIE spectrum band and target visibility range with constant factor of atmosphere transmission under no-precipitation conditions. Acquisition range R_acq and identification range R_id of preset probability are defined from the dependence of graphic ratio R = f(N_i; G_i) on the number of lines N of sight rod reticule corresponding to angular sixes A of standard height B at particular observation range R and on increase in G of night vision sight (HVS). HVS objective lens is optically coupled with camera zoom-objective and sight rod reticule. Image angular sizes of standard target are varied by means of photo camera mechanism with zoom-objective.

EFFECT: possibility to simulate tests of evaluation of disclosing properties of CIE.

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Description

The invention relates to the field of semi-natural simulation testing of combat individual equipment (BIE) and can be used for preliminary assessment in laboratory conditions of the unmasking properties of elements and sets of BIE military personnel in the near infrared (NIR) spectrum.

The unmasking properties of the elements and BIEs of military personnel in the NIR spectral region are estimated by the detection range D _obn and recognition D _{p of the} typical target - the growth figure of a soldier (RFU) on a typical natural background under normal observation conditions: level of horizontal natural night illumination (ENO) E _g = ( 3 ... 5) × 10 ^-3 lux, the directivity coefficient of illumination Р _е equal to the ratio of the vertical ЕНО (Е _в ) to the horizontal value, should be in the range from 0.7 to 0.9, the atmospheric transmittance per kilometer, τ _a must be at least 0.75, no precipitation.

A known method of determining the detection range and recognition of a small target in the NIR spectral region with night vision devices (NVD) based on field tests in real time. The method requires the involvement of a large number (up to 8-10 people) of participants, as well as significant periods of time (up to 3-5 days for one background), during which constant atmospheric conditions and the level of night illumination are required, and there is no precipitation. Field tests provide reliable information about the estimated parameters of the tested devices, but are associated with the implementation of a large number of range measurements in the field, i.e. require significant material and time costs, and in some cases, for example, with precipitation, fog and smoke, become unrealizable.

As analogues of the claimed invention, one can indicate a method for determining D _obn and D _p set forth in GOST P 50772-95 “Electron-optical night-vision devices. Methods for determining the parameters ", in the book A.V. Nozdracheva, V.P. Salnikova, M.V. Silnikova “Equipment”, St. Petersburg, Foundation “University”, 2001, p.16-17.

Closest to the claimed invention by purpose and essential features - the prototype - is a method of conducting a full-scale experiment to determine D _obn and D _p NVD in accordance with GOST P 50772-95.

The known method is a process coordinated in methodological, technical and organizational respects, which allows to determine the estimated parameters of the device (NVD) as a result of long-term and significant in volume tests on the ground.

However, the known method offers measurements on extended field paths in fixed normalized conditions and is highly dependent on natural weather conditions and the level of EHO. The known method is a planned process of full-scale tests, in which the measurement of range with a given probability is carried out by several operators when observing a standard target in the BIE in normalized night conditions, which is repeatedly moved by the test manager's command along the boundaries of a previously marked rangefinder route. This, ultimately, to obtain reliable results leads to a significant increase in test time and their volume.

The technical result of the invention is the ability to simulate tests to assess the unmasking properties of military equipment in the laboratory, which reduces the volume and time of field, in particular, polygon tests to assess the unmasking properties of elements and sets of military equipment in the NIR spectral region, and therefore accelerate the full scope of testing as an important stage in the life cycle of a new and (or) modernized set of combat individual equipment.

The specified technical result is achieved by the fact that in the known method of conducting full-scale tests to assess the unmasking properties of combat personal equipment (BIE) in the near infrared (NIR) region of the spectrum, in which the unmasking properties of the NII in the NIR spectral region are visually assessed by the characteristic features of a typical target observed in a night vision device (night vision device) on a natural background under normalized conditions with a given probability at the corresponding detection range D _obn and recognition range D _p , s According to the invention, the measurement of the estimated parameters is carried out in a closed laboratory, in which the normal observation conditions in the NIR spectral region are created by an artificial lighting system with the necessary level of night illumination, natural fragments of a typical natural background with steady-state spectral reflection coefficients in the NIR spectral region, and the target visibility with a constant atmospheric transmission coefficient in the absence of precipitation, the detection range value D and _upd dalnos and _Dr recognition with a given probability is determined from field trials in the plot of the resulting D = f (N _i; G _i ) the distance from the number of strokes N of the grid of the measuring world corresponding to the angular dimensions of a typical target of height B at a specific observation distance D, and from the increase of G NVD, the lens of which is optically connected to the zoom lens of the camera and the grid of the measuring world to measure the angular dimensions of the image typical targets placed on a common platform, while changing the angular dimensions of the image of a typical target is carried out by the camera mechanism with a zoom lens.

Estimated indicators D _obn and D _{p are} determined in laboratory conditions from the graphical dependence of the observation range on the number of strokes of the measuring world D = f (N _i ; Г _i ) corresponding to the angular dimensions of a typical target in the BIE at a specific observation distance, and on the increase in the device. These parameters are related to the known geometric dependence (1) between themselves and with the focal length of the lens of the device.

where B is the height of the target in meters;

Y - angular target size with the naked eye, etc .;

G = F ′ / f _ok - the increase in the device, krat;

F ′ is the focal length of the lens of the device, mm;

f _ok - the focal length of the eyepiece, mm

A statistical sample of the estimated indicators D _obn and D _{p is} obtained by changing the angular dimensions of the target image in the BIE by the mechanism of the camera with a zoom lens, assuming, in accordance with Ricco’s law, to maintain constant within certain limits the product of the brightness coefficient by the area of the image with small angular dimensions when changing sizes of this image.

The reduction in time and scope of tests for a preliminary assessment of the unmasking properties of combat personal equipment in the NIR spectral region is a consequence of the work:

firstly, in a limited area of a test laboratory with a length of 50 m;

secondly, regardless of the time of day or season of operation of combat individual equipment;

thirdly, in a laboratory with standardized observation conditions and a controlled environment free of various changing weather conditions available at open test sites;

fourthly, by changing the angular dimensions of the target in accordance with the range of its observation by the mechanism of the camera with a zoom lens;

fifthly, against the background of fragments of typical natural backgrounds (“deciduous forest with deciduous shrubs”, “green grass with a height of not more than 0.3 m”, “coniferous forest with a trunk height of not more than 4 m”), which retain their reflective properties ( spectral reflection coefficient) for a long time of observation (more than 9 months) almost unchanged, which gives the tests additional realism;

sixth, with special artificial lighting, which can be adjusted from dusk (1.5 lux) to various levels of ENO.

This allows you to significantly reduce the time and material costs of field testing of individual elements and sets of BIE due to the possibility of year-round assessment of the unmasking properties of BIE in the BIC region of the spectrum in laboratory conditions on typical natural backgrounds.

The analysis of possible methods for assessing the unmasking properties of BIE in the NIR spectral region allowed us to establish that the applicant has not found an analogue with features identical to all the essential features of the proposed method. The choice of a prototype from the found possible analogues made it possible to determine the set of salient features that are significant in relation to the technical result that is included in the claims. This gives reason to believe that the claimed method meets the condition of patentability "novelty."

The results of the search and research of well-known solutions in the field of evaluating the unmasking properties of small objects in the NIR spectral region in order to identify signs that match the distinctive features of the proposed invention from the prototype have shown that it does not follow explicitly from the prior art and regulatory documentation.

The invention is illustrated by drawings.

Figure 1 shows a structural diagram of a method of conducting full-scale model tests for a preliminary assessment of the unmasking properties of BIE in the NIR spectral region.

2 is a view of the grid with a scale division 0-01 installed in the world with a measuring optical parameters: the apparent increase telescopic system G ^x = 1, removal of the exit pupil from the last surface of the eyepiece q _O = 100 mm, the angular field of view in the object space - 10-13 °, the diameter of the exit pupil is not less than d _o = 20 mm.

Figure 3 shows the dependence of the number of strokes of the measuring worlds on the increase in the optoelectronic device for a specific observation range Д = f (N _i ; Г _i ).

The method of conducting full-scale model tests to assess the unmasking properties of BIE in the NIR spectral region is as follows. The measuring equipment is placed in the laboratory room (1) (figure 1). The goal (2) in the tested set of BIE is set at a distance of no more than one meter from a typical natural background (3). Using a light installation (4), the required level of EHP is created in the laboratory and measured with a control device (5). On a common platform mounted on a tripod, they place the NVD (6) with the given characteristics, the world measuring device (8) and a camera with a zoom lens (7) so that their optical axes coincide, and the operator (9), after turning on the NVD, could observe a distant target image on a natural background.

Then, to obtain a clear image of the target in the NIR region of the spectrum with a given criterion (detection - highlighting the target against a natural background in a limited time or recognition - confidently determining the type of target against a natural background in a limited time), the operator zooms in on the remote image of the target in eyepiece NVD. According to the grid of the measuring worlds (figure 2), the operator measures the value of the angular size of the received image. The magnitude of the angular size of the image of the target and the increase in NVD is determined by interpolation according to the schedule (figure 3) the corresponding value of the observation range. For a set of statistics, the same number of observations is repeated by several operators. When the number of correct answers of all observers for one level of illumination and natural background is at least 80% of the total number of observations, the tests are stopped. The time, conditions and result are recorded in a log.

The claimed invention was tested during testing of several sets and elements of combat personal equipment. With a significant reduction in time (up to 5 times) and the volume of tests, the relative measurement error in the laboratory compared to similar results in the field did not exceed 10% for ranges from 50 m to 350 m and 14% for ranges from 350 m to 500 m .

Thus, from the foregoing, the possibility of achieving the technical result claimed in the invention is confirmed, namely, reducing the time and scope of tests for a preliminary assessment of the unmasking properties of BIE in the NIR spectral region.

The industrial applicability of the invention is determined by the fact that the claimed method uses industrially manufactured measuring and optoelectronic devices, and the measuring world can be made on the basis of well-known components using modern technological equipment.

Claims (1)

A method for conducting full-scale model tests to assess the unmasking properties of combat personal equipment (BIE) in the near infrared (NIR) region of the spectrum, in which the unmasking properties of the NII in the NIR spectral region are visually assessed by the characteristic signs of a typical target observed in a night vision device (NVD) against a natural background in normalized conditions with a given probability at the corresponding detection range D _obn and recognition range D _p , characterized in that the measurement of the evaluated indicators is carried out in in an open laboratory room in which the normal observation conditions in the NIR spectral region are created by an artificial lighting system with the necessary level of night illumination, natural fragments of a typical natural background with steady-state spectral reflection coefficients in the NIR spectral region, the visibility range of the target with a constant atmospheric transmittance in the absence of precipitation, wherein the magnitude of the detection range L and _{upd Dr} recognition with a given probability range determined from the obtained oh in field trials graphic dependence D = f (N _i; G _i ) the distance from the number of strokes N of the grid of the measuring world corresponding to the angular dimensions of a typical target of height B at a specific observation distance D, and from the increase of G NVD, the lens of which is optically connected to the zoom lens of the camera and the grid of the measuring world to measure the angular dimensions of the image typical targets placed on a common platform, while changing the angular dimensions of the image of a typical target is carried out by the camera mechanism with a zoom lens.

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